1. Field of the Invention
The present invention relates to a method and means for releasably connecting the body of an electrical component such as a switch assembly to a support housing that extends alongside at least a portion of the body of the electrical componentxe2x80x94an example being the retention and proper positioning of a generally cylindrical body of an electrical switch that extends into the open rear end region of a tubular housing of a key operated lock that is adapted to operate the switch in response to the turning of a key inserted into a plug that is carried in an open front end region of the tubular housing. More particularly, the present invention relates to the use of a spring clip to releasably retain and properly position the body of an electrical component within a support housing, wherein the spring clip has resilient legs that extend through slots formed in opposite sides of the support housing and into engagement with formations that are provided on opposite sides of the body of the electrical component 1) to provide a secure yet releasable connection between the body and the housing, and 2) to bias the body of the electrical component into engagement with at least one stop formation defined by the support housing to ensure that the electrical component is held in a proper position relative to the support housing. An optional feature resides in providing the resilient legs of the spring clip with end formations that aid in retaining the spring clip in place on the housing by extending beyond the vicinity of the slots formed in opposite sides of the support housing to define leg end configurations that require at least some deformation or deflection of the spring clip in order to remove the spring clip from the support housingxe2x80x94a feature that helps to ensure that the switch assembly will not become disconnected from the housing due to vibration.
2. Prior Art
It is well known in the art to utilize tubular housings to connect a variety of types of electrical components to control panels. For example, signal lights and control switches often have tubular housings that are designed to be inserted through holes formed in control panels, and secured in place by spring clips or other types of fasteners.
Key operated electrical switches, referred to as xe2x80x9cswitchlocks,xe2x80x9d are among the various types of electrical control components that often are provided with tubular housings designed to be mounted in holes formed through control panels using spring clips or threaded fasteners such as nuts. The tubular housing of a switchlock typically has 1) an open front end region that journals a plug that defines a key-receiving opening and that can be rotated relative to the housing by turning the plug with a properly configured key inserted in the key-receiving opening, and 2) an open rear end region that receives the generally cylindrical body of an electrical switch that is operated when the plug is rotated by an inserted key.
Other types of control panel mountable electrical components also are known that are supported by rear end regions of tubular housings configured to be installed in openings formed through control panels, for example non-key-operated controls such as knob-operated switches, signal lights, small acoustical enunciators and the like.
Many of the electrical components that are provided with control-panel-mountable tubular housings are permanently connected to their housings. For example, the rear end regions of the tubular housings of switchlocks often are crimped to provide secure permanent connections with the bodies of their electrical switchesxe2x80x94or are otherwise permanently bonded or connected thereto by sonic welding or through the use of non-removable fasteners such as rivets.
Providing permanent, non-releasable connections between control-panel-mountable tubular housings and electrical components carried by rear end regions of the housings has the advantage of ensuring that the electrical components do not become disconnected from the housings due to vibration. However, these permanent connections may present serious drawbacks and disadvantages. Some control panel assembly, installation, removal, replacement and repair procedures are easier to perform if electrical components such as switch assemblies and any wires or other circuitry connected thereto can be separated from the support housings. When, for instance, a complex control panel is being assembled that is to include many closely spaced control-operated switches, it often is easier to mount the tubular support housings of these switches on the panel if the support housings have no switch assemblies (and no attendant wiring leads or other circuitry elements) connected thereto that get in the way of tools and fixtures that are needed to grip and position the support housings as fasteners such as nuts or spring clips are installed to hold the support housings in place on the control panel.
Likewise, when experimental setups of controls are to be updated by rearranging tile relative locations of switches and other electrical components, repositioning is easier to effect if the electrical components can be disconnected quickly from their support housings which are supported by an original control panel, and quickly reconnected to replacement support housings that are already mounted on a replacement control panel that orients the various electrical components in an improved arrangement or format.
It is known to utilize U-shaped spring clips to hold in place on control panels the tubular housings of switchlocks and other components that have having tubular housings. Examples of switch locks that can be held in place by U-shaped spring clips are found in such patents as U.S. Pat. Nos. 4,689,977, 4,633,689, 4,566,167, 4,427,852, 4,405,843 and 3,639,708 issued to Stanley C. Wolniak et al, referred to hereinafter as the xe2x80x9cSwitch Lock Patents,xe2x80x9d the disclosures of which are incorporated herein by reference.
It also is known to utilize a spring retainer clip to hold the rotatable plug of a lock within a surrounding tubular housing or barrel. The use of such a clip to fasten a key-receivable plug assembly within a surrounding barrel, with the retainer bridging complementary formations that are defined by the plug assembly and by the surrounding barrel is known. Features of a key-operable lock that employs such a spring-biased retaining mechanism are disclosed in U.S. Pat. No. 2,883,848 issued to Stanley C. Wolniak, referred to hereinafter as the xe2x80x9cPermanently Assembled Lock Patent,xe2x80x9d the disclosure of which also is incorporated herein by reference.
The use of a variety of groove-carried retention members that bridge from a groove that is formed in a portion of a key-receivable plug assembly to a complimentary groove that is formed in a surrounding portion of a barrel to fasten the plug assembly in the barrel is well known. In the above-referenced Permanently Assembled Lock Patent, such complementary grooves are provided near the rear end region of the plug assembly (i.e., complementary grooves carry a bridging retainer at a location that is spaced a substantial distance rearwardly from an enlarged diameter head formation that typically is provided near the front end region of the plug assembly). In some of the invention embodiments that are disclosed in the referenced Switch Lock Patents (e.g., in U.S. Pat. Nos. 4,566,167, 4,427,852 and 4,405,843), such complementary grooves are formed in peripheral surfaces of enlarged diameter head formations of the plug assemblies, and in surrounding barrel portions (i.e., complementary grooves carry retainers at locations that are near the front ends of the plug assemblies).
A need that is not well addressed by prior proposals is the provision of an easy-to-install, easy-to-remove method and means for connecting and disconnecting electrical components such as switches to the rear end regions of tubular housings that are mountable in holes formed through control panels. This need has become increasingly pronounced as the complexity and size of electrical switches and other assemblies of electrical components that need to be operated by control-panel-mounted knobs and key-operated locks has grown, many of which are far too sizable to be inserted through holes formed in control panelsxe2x80x94and as modern-day assembly practices have increasingly called for the tubular housings of electrical components such as key-operated switches to be mounted by automated equipment that is not well suited to feed delicate electrical devices having wires, terminals or other circuitry connected thereto.
The present invention addresses the foregoing and other needs and drawbacks of the prior art by providing a simple and inexpensive method and means for connecting the bodies of electrical components to the rear end regions of tubular support housings of the type designed for mounting in control panel openings or the like.
A feature of the present invention resides in the use it makes of a simple spring clip to provide resilient legs that are insertable through slots formed in opposite sides of the rear end region of a tubular housing and into engagement with formations provided on opposite sides of the body of an electrical switch that is at least partially surrounded by the tubular housing. The spring clip is easily installed, removed and reinstalled as may be needed to accommodate assembly, maintenance, repair and replacement procedures and the like.
A further feature of the present invention resides in the use it makes of a spring clip that performs the primary function of releasably connecting an electrical component to a tubular housing to also perform a secondary function, namely to bias the body of the electrical component toward and into engagement with at least one stop surface defined by the tubular housing. This feature is achieved by providing the housing and the body with non-aligned formations that are engaged by opposite sides of the legs of the spring clip, and by providing the resilient legs with a configuration that enables the legs to engage the non-aligned formations to effect this biasing action. Utilizing the curved legs of a spring clip to engage housing and body formations that are sufficiently aligned to permit the legs to connect the housing and the body to prevent disassembly, and yet are sufficiently non-aligned to define body and housing formations that are engaged by the legs to bias the body into engagement with a stop surface of the housing to properly position the body relative to the housing constitutes an advantageous arrangement of components that is not taught or suggested by prior proposals.
In preferred practice, a key operated switchlock has a tubular housing that carries a key operated lock assembly having a rotatable plug that extends into a forward end region of the tubular housing for operating a switch assembly having a body portion that extends into the rearward end region of the housing. The switch body is connected to the housing by a spring clip having curved leaf spring legs that not only extend into aligned slots formed on opposite sides of the housing and the body portion, but also preferably act to bias the switch assembly relative to the housing toward a seated position wherein an abutment formation connected to the switch body engages a stop formation connected to the housing.
An additional feature of preferred practice resides in the provision of distal end regions of the leaf-spring legs that aid in retaining the spring clip in place on the housing by extending beyond the vicinity of the slots to define formations that require deflection of the spring clip in order to remove the spring clip to release the connection between the switch assembly and the housing.